Classics, modern fiction, non-fiction and more. Written for secondary and adult students the Oxford Bookworms Library has seven reading levels from A1-C1 of the CEFR.br/br/Jewels are often at the hearts of big crimes: they are wanted by everyone because they are beautiful and valuable. These two stories are both mysteries about precious jewels which have disappeared. Where are the emeralds and the blue diamond, and who has taken them? Only one person can find the answers to these questions: Sherlock Holmes.br/br/CEFR: B1br/Word count: 11,150.